deleting files in hfs+ file systems, sigh...
OK, so I was on the command line and hit "prior command" and too quickly accidentally deleted a critical video i really wanted!!
so i had to try to recover the video frames from either my SD card or my laptop HD. i learned a lot -- how to "dd" both disk images, try sleuthkit/autopsy, some other recovery tools. for various reasons, nothing could find or restore the deleted video.
so then i got insane. i learned more about motion-JPEG and came up with a 21 digit hex string to look for. i found *all* motion-JPEG frames on my HD that were for *existing* videos, and found all frames on my HD that belonged to trashed items. (from there, i was able to recover all but the first few seconds of this movie i deleted, yay!)
but so what *this* movie is, is a concatenation of all the full and partial frames from *deleted* videos, that i found in my 72GB laptop HD scan. they are in "found byte position" order, and make a very surreal and most satisfying video.